This invention relates generally to security systems, and more particularly, to detecting the presence of and/or tracking animate objects within an area monitored by a security system.
Security systems typically use a variety of different detecting devices within a building or other monitored area. Motion sensors or detectors may be used to alert security personnel to the presence of an intruder. Unfortunately, motion detectors are deficient in pinpointing an intruder's specific location and do not provide adequate information if the person is stationary. Motion detectors also cannot identify the source of the motion, which may be an inanimate object falling from a shelf, a small animal, or personnel authorized to be in the area, and thus a false alarm may be generated, resulting in unnecessary deployment of personnel to check the area. Also, intruders may create diversions by activating motion sensors to draw security personnel away to a different area.
A security system may also use one or more video cameras to view desired areas. Analyzing the video content using a digital signal processor (DSP) is costly and requires a large amount of power. Complex techniques which burden a large DSP may be used to isolate an intruder within the video or image frame. The isolation processes may not work satisfactorily in low light or when the acquired video is low contrast, however, and the locations of people and/or animals may be difficult to detect.
Therefore, a need exists for a security system that can detect the presence of intruders and lower the number of false alarms. Certain embodiments of the present invention are intended to meet these needs and other objectives that will become apparent from the description and drawings set forth below.